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Does roofing sealant work on aluminum roofs and if so, what is the best brand to buy?

I have a 1988 Fleetwood 5th wheel trailer with an aluminum roof. The roof appears to be painted with a grayish material that is flaking off. There are several places where the rain leaks into the trailer. It also appears like a former owner tried to use silicone in several locations. Before applying anything new, I will use in industrial stuff bristled floor brush to remove the flaking material.

I assume all aluminum roofs have seams at regular intervals. My RV around 7 seams in the roof. I am thinking that leaking is mostly at the seams, because I notice a seam-crack in the "gray stuff" near the place with the worst leaking. Expansion/contraction could be a problem for the seams, because the RV is parked in direct sunlight. Using a temperature probe today, I measured 147F while the shad temp was 90F. A few weeks ago the shade temp was over 103F. When water was sprayed on the roof and I could hear creaking during the contraction.

The last time it rained, I covered the outside of the trailer with 2 mil painters tarp. The wind was not too bad and that kept out the rain but for a few drops.

Elastomeric roof sealer works fine on aluminum roofs and a 1988 metal roof is likley to have pinhole leaks by now. However, the seams are still the most likely culprit. You can use regular roof lap sealant on them, or Eternabond (or Dicor) tape.

The "gray stuff" sounds like a mobile home type of metal roof caulk. Nothing wrong with that, but it doesn't last forever.

Actually, this is probably one of the few places that stuff would actually work, but probably easier and cheaper to get a gallon or so of mobile home roof coat at the local hardware or home store and slobber it on.

I've attached a few pictures so that everyone can get a feeling of what is going on with my roof.

Picture #1: roof-main, This is what most of the roof looks like. A mixture of white and medium gray.

Picture #2: roof-flake, Here is a close-up of the medium gray flaking off.

Picture #3: roof-crack, This crack runs most of the width of the trailer. I don't know if it is the source of the leak, but the greatest leak is near that area.

Picture #4: roof-layers, I tool this picture where the TV antenna is mounted to the roof. It is informative because you can see the layers on the roof. Layer A - white is the bottom layer. I assume that the aluminum roof was white when it was manufactured. Layer B is silicone that was applied around the antenna mount. Layer C - gray is the coating that was applied to the roof. Layer D is more silicone applied on top of the gray coating.

Picture #5: roof-silicone, Here is a section of the roof where a lot of silicon was used.

Question 1: What are the advantages/disadvantages of using (mobile home roof coat)/(eternabond tape)

Question 2: Can I use both? If so, does it whether is I put the tape on top of the coating or the coating on top of the tape?

Question 3: Removing the flaking coating... There are places where the coating is flaking, but most of the gray coating does not appear to flake. I assume that plain water and elbow grease and s stiff bristle brush is the best way to remove the flaky bits. How much should I worry about part of the coating that appears well attached. If I use (mobile home roof coat)/(eternabond tape) is there a difference?

Question 4: Removing the silicone... There are a few places where the silicone is already peeling off, and there are are places where the silicone appears bonded to the factory painted aluminum roof. What is the best way to remove the silicone?. Should I be worried about stripping away the factory applied paint layer?

Question 5: Using the coating in sections... If I have to remove the silicon before applying the coating, I just don't see me doing it all in one day. The part where the leaking is the worst (the sleeping area, over the truck bed part), has very little silicon. Because of this, I would definitely prefer to work in a single section at a time. What are pros/cons of doing it this way.

Background: I am currently living in the RV in a stationary situation on my friend's land. I am currently in a financially tight situation, but my friend is willing to help out while I get back on my feet. In the future I am thinking about living and travailing in an RV. I don't know it it would be my current RV or if I will get a different one.